Gas-engine.



A. S. KROTZ.

Patented Aug. 17, 1909. 2 SHEETS-SHEET 1.

A. s.` KRoTz. .GAS ENGINE.

APPLICATION FILED PEB. 23,1907.

' '93 1 ,31 9. Patented Aug. 17, 1909.

2 SHEETS-SHEET 2.

ALvARos. KROTZ, :or CHICAGO, ILLINOIS.

GAS-ENGINE.

Specification of Letters Patent.

Patented Aug. 17, 1909.

Application filed February 28, 1907. Serial No. 359,779.

.To all whom 'it may concern:

Be it known that I, ALVARO S. Kno'rz, a-

citizen of the United States of` America, and a resident of Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Gas-Engines, of which the following is a spccitication.

rlhis invention relates to gas engines of the two-cycle type, and has for its object to provide a simple and efficient structural arrangement and formation of parts adapted to afford a very free outlet for the exploded gases from the engine, with a consequent free and effective operation of the engine, and in whichvthe incoming charge of explosive gases is adapted to very effectively expel the previously exploded gases from the engine cylinder, and with which the inlet and outlet ducts of the explosion chamber are adapted to open simultaneously, or approximately so, without danger. of back firing due to the ignition of the new charge by the old charge stillunder partialcompression, all as will hereinafter more fully appear.

AIn the accompanying drawings :-Figure Lis a vertical section of a gas engine embodying the present invention, and showing the piston at the end. of its up stroke. Fig. 2 is a similar view, with a piston at the end of its down stroke. Fig. 3 is a horizontal section on line 3-3, Fig. l.

Similar numerals of reference indicate like parts in the different views.

Referring to the drawings, l represents the closed crank chamber of the 'engine of any usual construction adapted to bearings for the mainy shaft, cylinderV and other parts of the engine, and which in some applications of the present invention will have a passage 2, for connection with the carbureter or other source of gaseous fuel supply, as common in gas engines of the two-cycle type. It is however preferable to arrange said inlet in the manner hereinafter described and for reasons hereinafter stated.

3, is the engine cylinder which may be -of `the air cooled or water cooled type, and

which in the4 present improvement has the head or top portion of its explosion chamber made of the hemispherical or dome .form shown, and provided with a central rentrant or downturned apertured portion or eye 4, in which is arranged the usual spark plug 5 of the engine; and as so constructed is adapted to coact with the other parts of the.

engine in the attainment of functions hereinafter more fully described. I

(5, is an annular exhaust chamber surrounding the engine cylinder at a .point immediately adjacent to the top of the engine piston when the same is at the end of its down stroke. Said exhaust chamber has communication with the interior of the engine cylinder, by a series of ports or pas sages 7 as shown, to afford an extended and free communication; and in addition said chamber is provided with an escape port 8 communicatingin any usual manner with the atmosphere.

9, isan annular Vsupply chamber surrounding the engine cylinder at a point immediately beneath the annular exhaust chamber 6 aforesaid. Such supply chamber has communication with the interior of the cylinder' by a series of ports or passages 10, as shown, to afford an extended and free communication between such chamber and the interior of the engine cylinder. ln addition said 'supply chamber is provided with an inlet passagev 1l adapted for connection with a carbureter or other usual source of gaseous fuel supply.

12, are a series of lateral ports or passages formed in the wall of the engine cylinder near the lower end of the same, and which are adapted to Vregister the closed crank chamber of the engine with the chamber of the hollow piston hereinafter described; the said lower end of the cylinder depending into the crank casing as shown for such purpose.

13, is the engine piston 'of an elongated and hollow form to provide a chamber of some capacity within the piston. The upper end of said piston is provided with a .central port controlled by a downwardly clos. ,Y

and spring held check valve 14, the seat .of which is preferably formed in .a bushing l5, screwed into said port as shown; such bushing is formed with an upwardlyY extending annular rim, which narrows toward its u per end, and is adapted to protect the valve fiom accident, as well as to constitute a nozzle for directing the incoming gases in a central col-umn into the explosion chamber of .the engine, as hereinafter more fully described. The .lower .end of the engine iston is .closed and has an inward cupped rm asshown,

to aord a compact pivotal connection .for the upper end of the engine pitman 16, to the said piston.

17, are a series of lateral ports formed in 5 the wall of the piston 13, near its lower end and forming an extended inlet'to the chamber of said piston, and adapted to intermittently register-with the series of ports or passages 12, in the lower end of the engine cylinder in the operation of the engine and form a communicationv between the crank case chamber and that of thepiston.

Assuming the piston is on a down stroke, the operation of the engine is as fol-lows:

sion ofthe gaseous contents of the crank casing is eiected, as usual in gas engines of the two-cycle type, with this difference, that in the present construction the inlet valve is not exposed to such pressure until the piston has practically reached the end of its downstroke, in which position the exhaust 1s open, and the ports .17, of the piston are in communication with the chamber of the crank casing to vpermit the compressed gases therein to pass through the chamber of: said piston and past the inlet valve 1st, of the explosion chamber in a retarded manner, due to frictional resistance to the passing gases, and the inertia of the valve aided by thc resiliency of its closing spring. Accordingly the exploded gases in the explosion chamber wil-l have time to exhaust down to practically atmospheric ressure before the incoming charge of exp osive gases enters the said explosion chamber, the result being that there will be no liability to back firing, as it is a Well established fact that the exploded charge in an engine explosion chamber when reduced to practically atmospheric pressure, will not ignite an incoming charge of explosive gases to cause back firing throu h the parts containing the gaseous fuel supp y of the engine. With the present construction the fresh charge of explosive gases enters the explosion chamber cent-rally 'as a round column, and passes to the top of said chamber where they are deflected outwardly and downwardly along the walls of said mainder of the exploded charge t rough the extended annular ports 7 provided by the present construction. With the engine piston moving upward, the charge of explosive gases within the explosion chamber 1s compressed, and as the piston practically reaches the end of its upstroke its lower end uncovers lthe inlet ports or assages 10, and permits a fresh sup ly cip gaseous fuel to enter the chamber o thecrank casing. Incidentally therewith the sparking mechanism will energize the spark plug 5 to cause an iiitionjof the ases in the explosion cham er to set up a resh cycle ofV the oper- 65 yations just described.

As the piston movesdownward a compreschamber tovery elfectively ex el the ref Additionaladvantages of the resent-improved" lconstruction are as fol ows:-The flow off'dfresh gaseous fuel'supply through the piston and engine cylinder in manner before described is adapted to aid materially 7d in cooling said parts, while the extent and arrangement of the exhaust ports insure the free and quick action -so very necessary in gas engines of the two-cycle type. The exhaust and inlet ports of the explosionV chamber are adapted to open at a practically simultaneous period, with safety, to, admit the new charge of explosive gases early and thereby give full or maximum power on the low speed of the engine. With an increase of engine speed the passageV of the gaseous fuel through the hollow piston into the explosion chamber s more and morevretajrded in relation to the opening of the exhaust; such retardation is due to the increased inerg5 tia of the inlet valve, the closing stress of its spring, and the progressively increased pressure on its upper area.. As a consequence the inlet of the explosive charge into the explosion chamber will vary automatically with the speed of the engine, and ppef vent in a very effective manner any liability" lto back firing. With the absence of such feature of automatic control, two-cycle engines as heretofore constructed have had their inlet and exhaust ports so arranged that the exhaust. port opens at a predetermined period in advance of the inlet port, in order to prevent such backfiring.

Having thus fully described my said invention what I claim as new and desire to secure by Letters Patent, is

l. In a two-cycle engine, the combination of a closed crank casing, an engine cylinder connected thereto, a chalnbered piston arv ranged in said cylindeiyand an inlet valve arranged in the upper end of said piston and controlling a port between-the chamber of the` piston and the combustion chamber of the engine, the piston having a lateral pas- 110 sage adapted to registerwith the chamber of the crank casing when the piston is in its lower position and establish communication between the chamber in the piston and the crank chamber, substantially as ,'set 115 forth.- l

2. In a two-cycle gas-engine, the combination of a closed crank casing, an engine cylinder connected thereto and. having its lower end depending into the crank casing ,and formed with a lateral port, a chambered piston arranged in said cylinder, and an inlet valve ,arranged in the upper end of' said piston and controlling a port between the chamber ofthe engine, thepiston havinga f lateral passage. adapted to register with the laforesaid lateral port inthe lower end'of the cylinder when the piston is'in its lower posi- -tion and establish-communication vbetween 130 chamber ofthe pistonv and the combustion v` the chamber in the piston and the crank chamber, substantially as set forth.

3. tionl of a closed crank casing, an engine cylinder connected thereto, a chambered piston varranged in said cylinder, an inlet valve 'arend ranged'in the upperend of said piston, and controlling a port between Athe chamber of the piston and the combustion chamber of the engine, and a spring .tending to `hold said valve in a closed position, the piston having alateral passage adapted to register with the chamber ofthe crank casing when the piston is in its lower position and estab lish communication between the chamber in the piston and the crank chamber, substantially as set forth. f

4. vIn a two-cycle gas engine, the combination of a closed crank casing, an engine cylinderconnected thereto and having its lower depending into the crank casing and formed with a lateral port, a chambered piston arranged in said cylinder, an inlet valve arranged in t-he upper end of said piston andcontrolling a port, between the chamber of the piston and the combustion chamber of the engine, a spring tending to hold said valve in a closed position, the piston having a lateralv piston and the crank chamber,

passage adapted to register with the aforesaid lateral port in the lower end of the cylinder when the piston is in its lower position and establish communication between the chamber in the substantially as set forth.

5.' In a two-cycle gas engine, the combination of a closed crank casing, an engine cylinder connected thereto and formed with a series vof outlet ports and an annular exhaust chamber, a chambered piston arranged 'in' said cylinder, and an inlet valve arranged in the upper end of said piston and con-i f trolling a port between the chamber of the -upper end of said piston and the combustion chamber of the engine, the piston having a lateral passage adapted to register with the chamber of the crank casing when the piston isin its lower position and establish communication between the Ichamber in the piston and the crank chamber, substantially as set forth.

. 6. In a two-cycle gas engine, the combination of a closed crank casing, an engine cylinder connected thereto and vformed with' a series (of outlet -ports and an annular exhaust chamber, a chambered piston arranged in said cylinder, an inlet valve arranged in the piston and controlling a port between the chamber of the piston and the combustion chamber of the engine, a spring tendingto hold said. valve in a closedposltion, the piston havin a, llateral passage. adapted to register with t e chamber of the crank casing when thepistonis in its lower u position and .establish `comrruinicatin be-I In a two-cycle gas engine, the combinai the combustion chamber Vof the series of inlet the upper end of said piston and controlling a port between thechamber of the piston and engine, the piston having a lateral passage .adapted to an engine cylregister with the chamber of the crank casing when the piston is in its lower position.

and establishl communication between the chamber in the piston and the4 crank chamber, substantially asset forth.

8.v In a. two-cycle gas engine, the combination or a'closed crank casing, an engme=cylinder vconnected thereto and formed with a chamber,l a chambered pistn arranged in said cylinder, an inlet valve arranged in the upper end of said piston and controlling a port'between the .chamber of the piston and the combustion chamber ofthe engine, a

spring tending to hold said valve in a closed position, the piston having a llateral passage adapted .to register with the chamber of the crank casing when the piston is in its lower position and establish communication between the chamber. in the piston` and the crank chamber, substantially as set forth.

9. In a two-cycle gas engine, the combina# tion of a closed crank casing, an engine cylinder connected' thereto, and formed with a series of outlet ports and anannular exhaust chamber and with a series of inlet orts and an annular supply chamber, a c ambered piston arranged in said cylinder,and an inlet valve arranged in the upper end of said piston and controlling a port `between the chamber of the piston and the combustion chamber of the engine, the piston having a lateral passage adapted to register with the chamber of the crank casing when the piston is in its lower position and establish communication between the chamber in the pis-- Y .ton and the-crank-chamber, substantially as set forth. I

l0. In a twocycle gas engine, the combination of ay closed 'crank easing, an engine cylinder connected theretoand formed with a series of outlet ports and an annular eX- haust chamber and with a series of inlet i ports and an annular supply chamber, a

chambered piston arranged in said cylinder, an inlet. valve arranged in the upper'end of said piston vand controlling/a port between the chamber of the piston and the combustion chamber of the engine,a spring-tending to hold said valve in a closed position, the

piston having a lateralpassage adapted to register with thel chamber'of the crank .cas-.

ports and an -annular supply.

, and a bushing forming a ing when the piston is -in its lower position and establish communication between :the chamber in'thel piston and the crank chambersubstantially as set forth.

l1. -l'n a two-cycle gas engine,l the .combination of a closedcrank casing, an engine cylinder -connected thereto and having a. dome shaped upperrend and a depending central portion, a chambered piston arranged in said cylinder, an inletvalve arranged in the npper end ofsaid piston Vand controlling a port between the chamber of the piston and the combustion chamber of the engine, seat for said valve and provided with an upwardly extending annular rim which narrows end, the piston having a lateral passage adapted to register with the chamber of the crank casing when the piston is in its lower position and tween Vthe chamber in the piston and crank chamber, substantially as set forth,

12. In a two-cycle gas engine,

the

nation of a closed crank casing, an engine l in 'said cylinder,

toward its' upper i establish communication be the combicylinder connected thereto and having a i dome shaped upper end achambered piston -arranged an inlet valve arranged in of saidpiston and controlling a port between the chamber of the piston and the combustion chamber of the engine, a bushing forming a seat for said valve and vprovided with an upwardly extending annular rim which narrows toward its upper end, and a spring tending to hold said valve in its" closed position, the piston having a 'lateral passage adapted to register with the chamber `of the crank casing when the piston is in its lowerpositionand establish communication between the chamber in the pisl ton-and the crank chai-uber, substantially as set forth.

central portion,

l the upper end l 'c l Signed at Chicago, Illinois. this th day i of February, 1907. il ALVARO SKR()TZ. l Vitnesses ROBERT BUnlvs, l HENRY Mor..

and a dependinv 

